The invention discloses a condensation-reboiling closed cycling method for superheated steam flow ultrasonic ultrafine-crushing tail gas and is applicable to occasions where crushing tail gas having the pressure ranging from 95 kPa to 125 kPa and the temperature ranging from 110 DEG C to 150 DEG C is produced after water-insoluble particles are crushed by a superheated steam medium having the pressure ranging from 1.2 MPa to 2.5 MPa and the temperature ranging from 280 DEG C to 420 DEG C. The tail gas is regenerated into clean and saturated steam having the pressure ranging from 105 kPa to 200kPa through pressurized condensation by the aid of a water-jet condenser and two-stage adiabatic reboiling by the aid of a condensation circulating fluid, and the mechanical energy required by ultrasonic gas flow ultrafine-crushing is provided through heating and pressurizing by the aid of a steam pressurizing machine, so that no boiler is used, primary energy sources for producing steam are saved, and the tail gas is purified in the cyclic regeneration process. A 2,000-kg/h superheated steam ultrafine-crushing device is taken as an example, according to the method, 200-kg/h standard coal isreplaced by 405-kW power for burning, the problems about waste heat discharging and cooling water consumption in existing superheated steam ultrasonic gas flow crushing technologies are solved, and aneconomical and applicable solution is provided for the low-carbon and environment-friendly technology progress.